It is oftentimes desirable to transmit data or information from one device to another without any physical connection therebetween. For example, in the case of a telephone set or the like, it may be desirable to transmit sound information received by the telephone from a remote source to a telephone user by way of some sort of ear piece without any wired connection between the ear piece and the telephone. In the case of a hard-of-hearing person wearing a hearing aid, it is advantageous to transmit the sound information from the telephone directly to such hearing aid. Likewise, it would be advantageous to transmit sound information from the telephone directly to a headset being worn by a person, to sound muffling gear being worn by an industrial or construction worker in a noisy environment, etc.
Especially in the case of a hard-of-hearing person wearing a hearing aid, it is known that such hearing aid may include an induction loop for receiving remotely generated induction signals. For example, such a hearing aid is disclosed in U.S. Pat. No. 4,361,733, hereby incorporated by reference. Such induction signals may be generated for receipt within a defined space such as a class room or auditorium. For example, a magnetic induction transmission system for transmitting to a hearing aid within a room is disclosed in U.S. Pat. No. 4,908,869, also hereby incorporated by reference.
Such induction signals may also be a by-product of an already-existing electronic device. For example, and as discussed in U.S. Pat. No. 4,908,869, it has been recognized that a typical telephone ear piece in a typical telephone handsets has a speaker that produces externally detectable audio-frequency magnetic (induction) fields correlated to the speech sound patterns created in such ear piece. Accordingly, a pick-up coil and related amplification circuitry have been included in hearing aids to detect such magnetic field signals and convert such magnetic field signals into sound signals to be directed toward the ear drum. In order to activate the pick-up coil and related circuitry, a hearing aid user simply flips a switch on the hearing aid unit.
Of course, such a system is not hands-free. The user having the hearing aid must actually pick up the telephone hand set and move the handset ear piece within range of the hearing aid so that the magnetic field generated by the ear piece can be detected by the pick-up coil in such hearing aid. Accordingly, a need exists for a hands-free inductive coupling interface for inductively coupling a telephone or the like to an inductive coupling link in a hearing aid or the like, wherein such inductive coupling does not require that a hearing aid user or the like pick up a handset or the like, and does not require that such hearing aid user or the like move the picked-up handset or other similar element within range of the hearing aid.